The aim of this research project is to determine the validity of Heart Tracking as a noninvasive method for evaluating myocardial contractility in man. This approach employs a device to track and record the motion and velocity alterations of the left ventricular border of the heart, by using radar type "track-while scan-techniques" applied to video signals from a portable fluoroscopic image intensifier. This system has been correlated by us in the animal with commonly accepted parameters of ventricular contractility. Preliminary studies in man indicate that this technique validly measures dynamic myocardial wall motion and velocity changes in various phases of the cardiac cycle. These observed contractility alterations were shown to be consistent with the absolute fiber shortening changes observed in the contracting ventricular muscle in various pre- and post-systolic phases of the cardiac cycle. In addition, during pilot on-line computer analyzed studies, observed tracking system changes in contractility provided much new information concerning interpretation of widely varying hemodynamic data. Predictions concerning recovery expectations could be made which aided the physician's assessment of total cardiac function. Additional correlations will be made in normal volunteer patients undergoing cardiac catheterization, patients with heart failure following open heart surgery or myocardial infarction with hemodynamic measurements in present use as well as other non-invasive measures of contractility, i.e. systolic time interval analysis. It is expected that this work will succeed in quantitating a simple, inexpensive, non-invasive technique for monitoring alterations in myocardial contractility in man during various phases of cardiac failure as well as providing a bedside aid for the rapid clinical assessment of optimal course of management in cardiac problem areas.